Disposable diaper

Abstract

A disposable diaper includes transversely opposite side edge regions thereof and the side edge regions are folded to form pleats each presenting a Z-shaped cross section and an body waste disposal sheet is bonded along its transversely opposite side edge regions to upper surfaces of the pleats so that the disposal sheet may be separated from the diaper as the transversely opposite side edge regions of the diaper are held and bilaterally pulled by a person having charge of body waste disposal with his or her hands.

What is claimed is:  
     
       1. A disposable diaper comprising: 
       an absorbent unit including:  
       a liquid-pervious topsheet;  
       a liquid-impervious backsheet; and  
       a liquid-absorbent core disposed between the topsheet and the backsheet,  
       said absorbent unit having a longitudinal center line, a front waist region, a rear waist region and a crotch region; and  
       a body waste disposable sheet removably bonded at least to said crotch region,  
       said absorbent unit being provided along transversely opposite side edge regions thereof with a pair of pleats that extend in a longitudinal direction, each of said pair of pleats having a Z-shaped cross section defined by a lower portion folded toward said longitudinal center line and an upper portion folded outward in an opposite direction to the direction in which said lower portion is folded and said body waste disposable sheet is removably bonded along transversely opposite side edge regions thereof extending in the longitudinal direction to said upper portions of the pleats so that said body waste disposal sheet is separated from said absorbent unit when said pleats are pulled in opposite directions.  
     
     
       2. The diaper according to  claim 1 , wherein said body waste disposal sheet is water-dispersible. 
     
     
       3. The diaper according to  claim 1 , wherein a bonding strength with which said body waste disposal sheet is bonded along the transversely opposite side edge regions thereof to said upper portions of said pleats, is lower than a tear strength of said body waste disposal sheet in its transverse direction. 
     
     
       4. The diaper according to  claim 3 , wherein said bonding strength of said body waste disposal sheet to the upper portions of said pleats is in a range of 30˜200 g/25 mm when said body waste disposal sheet is dry and is in a range of 20˜100 g/25 mm when said body waste disposal sheet is wet. 
     
     
       5. The diaper according to  claim 1 , wherein said lower portions of said pleats have a width of 10˜60 mm. 
     
     
       6. The diaper according to  claim 1 , wherein said pleats comprise a pair of side flaps that extend outward beyond transversely opposite side edges of said absorbent core. 
     
     
       7. The diaper according to  claim 1 , wherein said body waste disposal sheet is bonded to said upper portions of said pleats only in said crotch region so that portions of said pleats in said front and rear waist regions may be laterally unfolded without being restrained by the body waste disposal sheet.